PROJECT SUMMARY There is an urgent need for innovative approaches to adolescent obesity treatment, particularly among African Americans (AA), a population at increased risk of obesity and its associated morbidity and mortality. There is a particular dearth of research on the long-term efficacy of adolescent obesity treatments. Further, research and clinical practice guidelines consistently recommend that parents should be included in their adolescents' obesity treatment, yet the most effective strategy to engage parents in adolescent obesity treatment remains unclear. Towards that end, this investigation, (informed by R21HD084930), will conduct a fully-powered, randomized controlled trial, to examine the efficacy of two distinct approaches to involving parents in their adolescents' obesity treatment. Participants will be 210 12-16 year old adolescents (BMI>85th percentile) and parents (BMI>25 kg/m2) with overweight or obesity. Families will be randomized to one of two 4-month treatments: 1) TEENS+Parents as Coaches (PAC), engaging parents as helpers in their child's weight management via parent skills training, or 2) TEENS+Parent Weight Loss (PWL), engaging parents in their own behavioral weight management. All adolescents will participate in the TEENS+ protocol, which includes nutrition education with dietary goals, supervised physical activity, and behavioral support, and integrates motivational interviewing to enhance treatment engagement. Assessments of anthropometrics, dietary intake, physical activity, parenting and home environment variables will be completed at 0, 2, 4, 8, and 12 months with the primary endpoint at 12m follow-up. Results of this investigation have the potential to significantly advance science in this area and ultimately inform clinical practice guidelines related to the role of parents in adolescent obesity treatment.